申请人:The Florida State University Research Foundation, Inc.
公开号:US20160347778A1
公开(公告)日:2016-12-01
Disclosed are methods for rerouting radical cascade cyclizations by using alkenes as alkyne equivalents. The reaction sequence is initiated by a novel 1,2 stannyl shift which achieves chemo- and regioselectivity in the process. The radical “hopping” leads to the formation of the radical center necessary for the sequence of selective cyclizations and fragmentations to follow. In the last step of the cascade, the elimination of a rationally designed radical leaving group via β-C—C bond scission aromatizes the product without the need for external oxidant. The Bu
3
Sn moiety, which is installed during the reaction sequence, allows further functionalization of the product via facile reactions with electrophiles as well as Stille and Suzuki cross-coupling reactions. This selective radical transformation opens a new approach for the controlled transformation of enynes into extended polycyclic structures of tunable dimensions.
披露了一种利用烯烃作为炔烃当量重新定向自由基级联环化的方法。该反应序列由一种新颖的1,2 锡移位引发,实现了在过程中的化学和区域选择性。自由基的“跃迁”导致了形成所需的自由基中心,以便后续选择性环化和断裂序列的进行。在级联的最后一步中,通过β-C—C 键裂解消除经过合理设计的自由基离去基团,使产物芳香化,无需外部氧化剂。在反应序列中安装的Bu3Sn基团允许通过与亲电试剂以及Stille和Suzuki交叉偶联反应进行容易反应来进一步对产物进行官能化。这种选择性的自由基转化开辟了一种新的方法,用于将炔烯控制地转化为可调尺寸的扩展多环结构。